Malicious PDF — malware analysis report

Static analysis result for SHA-256 d9b44077f4e74945…

MALICIOUS

PDF

74.1 KB Created: 2021-09-14 00:50:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e6c99e3382f2efdda05ac16976a5bd4e SHA-1: 096981b31720e0a947c382302d583bf68bc7b72c SHA-256: d9b44077f4e749455443e8cf8b0770f9415737a3d0ae0e3150b0eb9382e92214
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains embedded JavaScript, which is often used to exploit PDF vulnerabilities or redirect users to malicious sites. The presence of numerous external URLs, many hosted on disposable domains and employing UTM parameters, suggests a phishing or malware distribution campaign. The primary attack pattern involves using the PDF as an initial lure, likely via spearphishing, to engage the user and subsequently download or redirect to a malicious payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://allytemp.ru/uplcv?utm_term=apk+lucky+patcher+root PDF link annotation
    • https://hashtag.school/userfiles/file/kupoteveridimamelexer.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613149a088c48---9666784953.pdfIn PDF document text
    • http://altelaw.com/uploads/image/file/mobewuworadapetoro.pdfIn PDF document text
    • http://myblindz.com/fck_user_files/file/vobudodawik.pdfIn PDF document text
    • http://doudou.tw/userfiles/files/kabemapewonex.pdfIn PDF document text
    • https://palezieux.com/ckfinder/userfiles/files/gigakijenema.pdfIn PDF document text
    • http://www.papelerialapiceros.es/ckfinder/userfiles/files/14318492385.pdfIn PDF document text
    • https://www.oalysa.cz/ckfinder/userfiles/files/97998445790.pdfIn PDF document text
    • http://henanshuangxin.com/d/files/sixudamas.pdfIn PDF document text
    • https://trungtammatnamviet.vn/upload/files/dolufalunami.pdfIn PDF document text
    • https://satybharat.com/ci/userfiles/files/44385155610.pdfIn PDF document text
    • http://zgic.ru/!upload/files/kalumik.pdfIn PDF document text
    • http://xn--b1agjlwjc3g.xn--p1ai/ckfinder/userfiles/files/lesalenafosusif.pdfIn PDF document text
    • https://www.fibertech1.com/my_content/js/ckfinder/userfiles/files/31537098090.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c15799018f---29151934344.pdfIn PDF document text
    • http://autowagon.it/userfiles/files/vunifojotomukusa.pdfIn PDF document text
    • http://sungwoo-n.com/userfiles/file/9022556218.pdfIn PDF document text
    • https://perfecthospital.net/ckfinder/userfiles/files/mamigiliva.pdfIn PDF document text
    • http://skrutit-probeg.ru/upload_picture/file/wejurizudilitozesonuxezuz.pdfIn PDF document text
    • http://urduhadith.org/survey/userfiles/files/4266192752.pdfIn PDF document text
    • http://alburigiott.it/userfiles/files/bujuwafudab.pdfIn PDF document text
    • http://www.idukkidiocese.org/files/js/ckfinder/userfiles/files/kategaguki.pdfIn PDF document text
    • http://pnmanagementsolutions.in/uploads/jateweridutotulamimelune.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b886.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB886 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d098.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD098 18636 bytes
SHA-256: f63f610503d19d5d439c6bf6b460e8b791867759362d90122727ef230c7968ec
font_02_sfnt_off0001014e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1014E 10392 bytes
SHA-256: 45ab95a5a5fcf6d78c2bed3558b4f260016387d326212ad4cac0e355aff13433